/**
 * L2FProd.com Common Components 6.9.1 License.
 *
 * Copyright 2005-2011 L2FProd.com
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.l2fprod.common.swing;

import java.net.URL;
import java.util.HashMap;
import java.util.Map;

import javax.swing.Icon;
import javax.swing.ImageIcon;

/**
 * IconPool.<br>
 *
 */
public class IconPool {

    private static IconPool iconPool = new IconPool();

    private Map pool;

    public IconPool() {
        pool = new HashMap();
    }

    public static IconPool shared() {
        return iconPool;
    }

    /**
     * Gets the icon denoted by url.
     * If url is relative, it is relative to the caller.
     * 
     * @param url
     * @return an icon
     */
    public Icon get(String url) {
        StackTraceElement[] stacks = new Exception().getStackTrace();
        try {
            Class callerClazz = Class.forName(stacks[1].getClassName());
            return get(callerClazz.getResource(url));
        } catch (ClassNotFoundException e) {
            throw new RuntimeException(e);
        }
    }

    public synchronized Icon get(URL url) {
        if (url == null) {
            return null;
        }

        Icon icon = (Icon) pool.get(url.toString());
        if (icon == null) {
            icon = new ImageIcon(url);
            pool.put(url.toString(), icon);
        }
        return icon;
    }

    public synchronized void clear() {
        pool.clear();
    }

}
